AA/AMPS copolymer

AA/AMPS copolymer (CAS 40623-75-4) is a synthetic anionic polymer combining acrylic acid and AMPS monomers; also marketed as Acrylic acid-AMPS copolymer.

Where is AA/AMPS copolymer used?

• Industrial water treatment: scale inhibitor and dispersant against calcium carbonate, calcium sulfate and calcium phosphate in cooling towers, boilers and reverse osmosis systems
• Textile and paper processing: dispersant and sequestrant preventing mineral deposition during dyeing and bleaching
• Home care and industrial cleaning: builder and anti-redeposition agent in detergents
• Personal care: rheology modifier and stabilizer in gel-based and emulsion systems
• It acts as a threshold agent where conventional polyacrylates underperform under high hardness, temperature or pH.
• Scale inhibitor and dispersant in oilfield refill water systems.
• Disperses iron oxide and silt in metallurgical and steel plant high heat-exchange systems.
• Pulp scale inhibitor in the papermaking industry to prevent mineral deposition.
• Remains useful up to about 150 °C, with scale inhibition maintained across a wide pH band.

Good to know: Specifications vary by molecular weight and monomer ratio; confirm with suppliers for the target application.

Formulation notes

• Compatible with organophosphonates such as HEDP, ATMP and PBTCA, and with zinc salts, over a pH range of about 7.0 to 9.5.
• For reverse osmosis pretreatment and boilers, the dosage is typically 10 to 30 mg/L, adjusted according to water analysis and system concentration ratio.
• Often used together with HEDP: the phosphonate controls calcium carbonate while the polymer stabilizes phosphate and zinc.
• Unlike polyacrylic acid, remains soluble and active at high calcium concentrations instead of precipitating as a calcium polyacrylate gel.

Typical specification

• Molecular weight ranges from about 1,000 to 20,000 depending on grade.
• Solid content is 30% or 40%.
• Density at 20°C is 1.05 or 1.15 g/cm3.
• pH of a 1% aqueous solution is 0.100~2.5 or 3.5~4.5.
• Solid content is minimum 30.0% for one grade and minimum 40.0% for another grade.

Regulatory status

• CAS 40623-75-4 applies to the copolymer in free acid form, while a sodium salt grade may carry a different identifier.
• Most suppliers present it as non-regulated, and it is generally not considered a dangerous good for transport.

Storage, packaging and handling

• Commonly shelf life is ten months.

Frequently asked questions about AA/AMPS copolymer

What is the minimum solid content of the powder form?

AA/AMPS powder form has a minimum solid content of 95%.

What form is AA/AMPS copolymer supplied in?

It is supplied as a colorless to light yellow viscous liquid.

Technical content is compiled and updated by the SoleChem product team from public technical sources; the certificate of analysis (COA) governs product-specific specifications.